Cellular communication networks evolve towards higher data rates, together with improved capacity and coverage. In the 3rd Generation Partnership Project (3GPP) standardization body, several technologies have been and are also currently being developed.
LTE (Long Term Evolution) is a recent standardised technology. It uses an access technology based on OFDM (Orthogonal Frequency Division Multiplexing) for the downlink and Single Carrier FDMA (SC-FDMA) for the uplink. The resource allocation to wireless terminals (also known as user equipment, UEs) on both downlink and uplink is generally performed adaptively using fast scheduling, taking into account the instantaneous traffic pattern and radio propagation characteristics of each wireless terminal. Assigning resources in both downlink and uplink is performed in the scheduler situated in the radio base station.
For transmissions of audio data, as for all data over wireless interfaces, there are occasions when data is lost, e.g. due to path loss, interference, etc. When an audio frame is lost, a receiving audio decoder can detect the lost audio frame and can then perform a packet loss concealment (PLC) procedure to generate audio which as good as possible reduces the effects of the lost packet on the audio.
However, there are several possible PLCs procedures and it would be beneficial to correctly select what PLC procedure to use in different situations.